Gleaning salt-wells



UNITED STATES PATE-'NT OFFICE.

JOHN MASON, OF EAST SAGINAW, MICHIGAN.

CLEANING SALT-WELLS.`

SPECIFICATION forming part of letters Patent No. 224,024, dated February 3, 1880.

Application led April 1, 1879.

To all whom it may concern Y Be it known that I, JOHN MASON, of East Saginaw, in the county of Saginaw and State of Michigan, have invented an Improvement 5 in Cleaning SaltsWfells, of which the following is a speeitication. a The nature of my invention relates to an improved method or process of Vcleaning saltwells in which the iow of brine is obstructed.

` Saltwells are bored through the various strata of clay and rock, through the lime-rock overlying the salt-bearing rock, and into the underlying shales. Iron tubing ,is then inserted from the top, in successive lengths, until the lower end of the bottom length reaches the lime-rock, which almost invariably overlies the salt-bearing rock. This latter-named rock is iissured, and the brine finds an outlet through the fissures into the well, whence it is withdrawn by pumping. In the course of time it is found that' the well runs dry, or nearly so. This is occasioned by the bleeding, as it is technically termed, of the 4overlying strata, which contain gypsum, iron, and other soluble substances, which drip down and, with the rust of the iron piping, gradually form a coating upon the wall ot the bore through the saltbearing rock 'until the fissures therein are closed, to the exclusion of the brine. In order to remove this thin coating, it has been the practice to insert av suitable tool attached to a rod and realn out the bore through the salt-bearing rock, thereby removing the scale. Each time this is done the bore through this/salt-bearing rock is slightly increased in Adiameter until the tool, which cannot be larger than the bore of the iron piping above, will be requiredito be so correspondingly increasedin size that it cannot be inserted through the In this case the pipe lmust be removed as such wells are several and then be `replaced 4after the salt-bearipg rock -has been'reamed out. Thegr'eat depth at which this rock is found and the necessity of using jointed rods to operate the reaming-tool prevents the practicabilityof using an expanding tool for the purpose of removing the', scale. As the salt-bearing rock is usually from ninetyto one hundred feet thick, and the bore through it becomes coated its whole length,

pipe. at a large expense, hundred feet deep, the bore throughthe explosion of a torpedo at the bottom, as is done in oil-wells, would not produ/ce the desired result., for the effect produced would be conlined to a given radius from the 'point of explosion.

The object of my invention is to obviate. all these difficulties by thefollowing very cii'cctive method.

Figure l is a vertical central section of a saltfgwell from the top of the overlying limerrock, at which the iron piping ceases, to the bottom of the well, and showing the tissures in the salt-'bearing rock. Fig. 2is `a like view, showing the ssures and bore through the salt-bearing rock coated with thedrip from above.

In the accompanying drawings, which form a part of this specitication, A represents the usual stratum oflime-rock overlying the saltbearing rockB. C represents the underlying shale, and D a redshale, in which the bore of the well usually terminates. The section of the well between thesurface and th'e lime-rock A is not shown. This is the section hereinbefore referred to whichis tubed with the iron pipe spoken of above.

E represents an insulated electrical wire, which is connected with Aa battery, F, at the surface. This wire is of sufficient length to reach to the bottom of the well, where its end b is left exposed andforms a ground-connec-- The battery-F also has a-groundcon nection, asshown at c. Near the lower end of the wire E, and about at the bottom of the salt-bearing rock, is attached tosuch wire a small torpedo, lot, and above this torpedoarc strung upon such Wire a series of small torpedoes, a', placed at suitable intervals apart, the upper torpedo ot' the series being nearthe top of the salt-bearing rock.

To attach the torpedoes to the wire they are cut in halves in the direction of their length. Each half is then placed against the covered insulated wire which passes through each torpedo, as shown. yThe torpedoes are then tied in a proper manner to the insulated. wire at the desired distances apart. The lowest torpedo, a, contains an electrical exploder, of any y usual construction, the covering of the wire E being removed and the wire exposed at that point for contact with the exploder.

tion.

IOO

In erploding'the,torpedoes the upper'tor-gl j pedoesare'not affected by the electrical current which vpasses to, and explodes the lowest torpedo, a; while the, torpedoes above are ex'- f ploded -in suc cession, .each by the concussion caused bythe explosion ofthe torpedo next.'

below. 5 The torpedoes,'beingdesignedisiniply yto break up and' remove the coating' from the bore of the well, should-be quite small, and,

placediat such-a distance apart that Ythe'w'hole` -s coating will be removed without causing any unnecessary breakingdown of the walls of the .w'elL f l It -will bei seen' that,the well. beingbored, whollythrough tli'esalt-bearb) g. rock" a dis tance' usually of ninetyor one hundrellfeet, a single torpedo of sufiicient length to affect the Wholebore through s uch rock. would protheV well unsuitablefor use., .'W'ith-'the smallduce agreater'explosion than wouldbe necessary for the purpose of simply removingthe coating, and would break down,- the 'walls of thewellto such an=extent as to soon render torpedoes, ho we'i'er,placed at certain distances apart,fth1s damage-isavoided, since the force ofthe explosion can regulated to a nice degree.

Sy exploding 4,lowest torpedctirst land the othersabove :in succession a better result Tis' obtained, sinc'ejlif vthe upper torpedo were first exploded, the'bore ofthe well being. small,

' the dbris would fall down and` lill the bottom of the well, so

I ofthe eX-plo'sion of the lowest torpedo.

j In practice, the-pump being're1noved,.1ths' wire- E, withfthe series of` torpedoes attached,

yformed' the coating.

as to lesseng'or destroy the eifect is lowered into the well, and asl the distance frornthe surface to the bottom of thesalt-rock I l is known, the torpedoes are 'easily placed inposition.

ing thebrine to ilow into the well. The wire is then withdrawn, first having been. discon- 5 nected from't-lic battery, and the pump replaced.

in the' salt-bearing rock are disclosed, allowbe found `to withdraw the materials which,

What I claim as` my'invention, and desire to secure 'by Letters Patent, is-

1. The methodotl removing theeoating from n'u'nil'erfjofsmall torpedoes, a' a', placed. at intervals in `the bore through the sal t-bearin g rock,'substa ntially as described.v

` 2." 'll-he means for remox'ing the coating from the Walls of :salt-wells, consisting of the insulated wire E, lthe series of small torpedoes a u', the lowesttorpedo containing an electrical explder, the -battery F, and ground-connections'b 0, substantially as described and' shown.

the walls of saltwe1ls,..consisting in exploding in succession, commencingr with the lowest, a 6o 

